This invention relates to a process for depositing and etching of copper in the formation of multi-layer structures, and more particularly to an integrated process for conducting such copper deposition and etching operations, particularly in the formation of semiconductor devices.
Copper would be useful in the metalization of multi-layer structures such as semiconductors and the like. A number of technology problems must be overcome before widespread use of copper can be achieved. For example, there is no reliable process for the deposition and etching of copper.
A CVD process has been employed for metalization of copper. In U.S. Pat. No. 5,087,485, for example, a copper diketone, such as hexafluoroacetylacetonate (hfac), is employed in a CVD process to coat a heated substrate with copper. An alcohol compound having an alpha hydrogen is used to catalyze the copper deposition. Various copper film deposition processes using copper(hfac) are outlined in U.S. Pat. No. 5,087,485, column 1, line 26 through column 2, line 7. A CVD process for the deposition of copper Cu(hfac) and vinyltrimethylsilane is also provided in an article by H.K. Shin, et al in Mat. Res. Soc. Proc., Vol. 204, page 61 (1991) entitled "SYNTHESIS OF NEW COPPER(I) BETADIKETONATE COMPOUNDS FOR CVD OF COPPER".
Therefore, although processes for the deposition per se of copper are known, a need exists for a reliable integrated copper deposition and etching process.